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4ch Plane with Retactable Landing Gear

This is the most mechanically complicated plane I've ever built. It has a wing span of 9.5", weighs 4.25g, has full flying rudder and elevator, and retractable landing gear.

Flight times on this airplane are in the 7-10 minute range with a 30mAh single cell lithium polymer battery. The frame is all made from carbon fiber rod or tube in the 0.5mm - 1.5mm range. The covering is OS film and is 0.5-1 micron thick.

The propulsion system uses a 4mm 10ohm motor, geared down 6:1, driving a 3.25" carbon fiber propeller. The servos that drive the rudder and elevator are each 400mg and are my own custom design. Oh, and the tail wheel is steerable.

Ground handling on this plane is amazing and arguably the most fly part of not-flying it. Landing gear is very very uncommon on micro planes. So, being able to do things like take offs, landings, and touch & goes just makes this plane very cool. When it does get in the air it flies very slow. Although, it has enough thrust to get going pretty fast or climb in altitude. The thrust-to-weight ratio is over 75% as I recall.

The landing gear retract mechanism also uses a custom servo of my own design. It is designed to retract the landing gear parallel to the fuselage and deploy them at an angle. The entire mechanism as show below weighs around 0.25g.

Here is a video showing a close up of the airplane with all the moving bits in action. The next video shows it in flight.

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Other People Thought These Were Cool..

What better way is there to spend multiple consecutive weekends than sitting at your computer, redesigning a mechanism that has existed for decades, all to be able to 3D print something that can be bought at the store for less than $1? ... That's right, anything. However, when your co-worker throws down the gauntlet there is only one thing to do. Take it up.

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